SQL Server：将历史数据转换为临时表答案

【问题标题】：SQL Server : convert historical data to Temporal TablesSQL Server：将历史数据转换为临时表
【发布时间】：2017-05-02 20:15:22
【问题描述】：

我们拥有 SQL Server 2016。多年来，我们拥有自己的历史。现在我想将历史数据转换为新格式，并将 CustomAudit 表用作包含已有历史数据的历史表。

一开始会有一个小例子，然后是问题

CREATE TABLE [dbo].[client]
(
     idclient int identity(1,1) primary key, 
     clientData nvarchar (400)
) ON [PRIMARY] 

INSERT [dbo].[client] ( clientData ) values ('some-12221')
INSERT [dbo].[client] ( clientData ) values ('some-22111')

alter table [client] 
add 
    StartTime datetime2 GENERATED ALWAYS AS ROW START  DEFAULT GETUTCDATE(), 
    EndTime datetime2 GENERATED ALWAYS AS ROW END DEFAULT CONVERT(DATETIME2, '9999-12-31 23:59:59.9999999'), 
    PERIOD FOR SYSTEM_TIME (StartTime,EndTime) 

CREATE TABLE [dbo].[CustomAydit_client]
(
    idclient int,
    dEditDate datetime NOT NULL DEFAULT (getdate()), 
    clientData nvarchar (400)
) ON [PRIMARY] 

alter table [CustomAydit_client] 
add 
    StartTime datetime2 GENERATED ALWAYS AS ROW START  DEFAULT GETUTCDATE(), 
    EndTime datetime2 GENERATED ALWAYS AS ROW END DEFAULT CONVERT(DATETIME2, '9999-12-31 23:59:59.9999999'), 
    PERIOD FOR SYSTEM_TIME (StartTime,EndTime)

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (1, (CAST(N'2016-05-06 10:08:11.923' AS DateTime)), 'some-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (1, (CAST(N'2016-02-11 10:08:11.923' AS DateTime)), 'some-211')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (2, (CAST(N'2016-12-06 10:08:11.923' AS DateTime)), 'some-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (1, (CAST(N'2015-05-19 10:08:11.923' AS DateTime)), 'some-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (2, (CAST(N'2016-05-06 10:08:11.923' AS DateTime)), 'some-211')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData)
VALUES (1, (CAST(N'2016-05-26 10:08:11.923' AS DateTime)), 'some-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (2, (CAST(N'2016-05-06 10:08:11.923' AS DateTime)), 'some33-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (1, (CAST(N'2016-05-06 10:08:11.923' AS DateTime)), 'some3-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate,clientData) 
VALUES (2, (CAST(N'2016-11-16 10:08:11.923' AS DateTime)), 'some-1')

INSERT [dbo].[CustomAydit_client] (idclient, dEditDate, clientData) 
VALUES (1, (CAST(N'2016-02-17 10:08:11.923' AS DateTime)), 'some-1')

我需要行和行的 StartTime。

对于客户 1，我想获取字段 DeditDate 的第 2 行数据

更新此数据第 1 行字段 EndTime

最后一行，客户端不应该有 EndTime，这可以 9999-12-31 23:59:59.9999999

SELECT
    ROW_NUMBER() OVER( PARTITION BY idclient ORDER BY dEditDate) AS tempid,
    idclient,
    dEditDate,
    StartTime, EndTime
FROM
    [dbo].[CustomAydit_client]
ORDER BY
    idclient, dEditDate

【问题讨论】：

您在发布表定义和示例数据方面做得很好。但我不太清楚你想要什么作为输出。
在您需要 StartTime 和 EndTime 的行的临时表中。我不知道如何正确地完成 EndTime。使用我的数据
我需要这样1drv.ms/i/s!ApEvwFL7i3nmkvlgTivat9If6J_vdQ
不确定该图像应该向我显示什么。您的输出看起来与输入的数据相同。或者您是否试图使结束日期成为“下”行的开始日期值？？

标签： sql sql-server sql-server-2016

【解决方案1】：

您可以使用lead 函数从下一行获取一个值作为结束时间。

select 
    ROW_NUMBER() OVER(PARTITION BY idclient ORDER BY dEditDate) AS tempid,
    idclient,
    dEditDate,
    StartTime,
    lead(dEditDate) over(PARTITION BY idclient ORDER BY dEditDate) as EndTime
from [dbo].[CustomAydit_client]
order by idclient, dEditDate

【讨论】：

你对lead在很多行（超过100 mio）的情况下的性能有什么经验吗？
谢谢你能帮我很多
@GoAnatol，你得到你的问题的答案了吗？我需要完全相同的东西